MAC flapping-based loop detection is a method for detecting Ethernet loops based on the frequency of MAC address entry flapping.
Generally, redundant links are used on an Ethernet network to provide link backup and enhance network reliability. Redundant links, however, may produce loops and cause broadcast storms and MAC address entry flapping. As a result, the communication quality deteriorates, and communication services may even be interrupted. To eliminate loops on the network, the spanning tree protocols or Layer 2 loop detection technology was introduced. If you want to apply a spanning tree protocol, the protocol must be supported and you need to configure it on each user network device. If you want to apply the Layer 2 loop detection technology, user network devices must allow Layer 2 loop detection packets to pass. Therefore, the spanning tree protocols or the Layer 2 loop detection technology cannot be used to eliminate loops on user networks with unknown connections or user networks that do not support the spanning tree protocols or Layer 2 loop detection technology.
MAC flapping-based loop detection is introduced to address this problem. It does not require protocol packet negotiation between devices. A device independently checks whether a loop occurs on the network based on MAC address entry flapping.
Devices can block redundant links based on the frequency of MAC address entry flapping to eliminate loops on the network.